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【新文速递】2023年10月24日复合材料SCI期刊最新文章

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今日更新:Composites Part B: Engineering 1 篇

Composites Part B: Engineering

Effects of surface characteristics and alkalinity on the deterioration of BFRP bars and BFRP-SSC interface in seawater environment

Feng Guangyan, Guo Shuaicheng, Zhou Linlin, Luo Wenheng, Guo Xiangke, Jin Zuquan, Zhu Deju

doi:10.1016/j.compositesb.2023.111072

表面特性和碱度对海水环境中 BFRP 棒材和 BFRP-SSC 界面劣化的影响

This study investigated the surface characteristics and concrete alkalinity on the deterioration of basalt fiber reinforced polymer (BFRP) bars and the interface between BFRP bars and seawater sea-sand concrete (SSC) in a seawater environment. The degradation of BFRP bars with three surface characteristics (sand coating, helically-wound, and helically-wrapped) embedded in two alkalinities of SSCs and BFRP-SSC interface were studied by shear, tensile, and pull-out tests, respectively. Additionally, the microstructure of the BFRP and BFRP-SSC interface was characterized by Fourier transforms infrared spectroscopy (FTIR), X-ray computed tomography (X-CT), and scanning electron microscope (SEM). The experimental results showed that sand-coated BFRP bars exhibit the best durability performance among the three types of BFRP bars due to forming a protective layer of sand and the helically-wound BFRP bars degrade from the groove (rich fiber and less resin protection zone). The degradation of BFRP bars in low alkalinity (LA) SSC is significantly mitigated owing to the reduced alkalinity. Furthermore, the hindering effect of the sand layer also enhances the bond durability between bars and SSCs compared with the other two types of BFRP bars. The bond strength between BFRP bars and LA-SSC is slightly reduced after 180 days of seawater immersion, while that in ordinary (O) SSC decreases significantly. The pull-out failure of sand-coated BFRP bars in LA-SSC is wearing out of the sand layer and surface resin after environmental conditions, while that of helically-wound BFRP bars in LA-SSC are peeling off ribs. The research outcomes can serve as solid base for employing BFRP bars in the marine environment.

本研究探讨了在海水环境中,玄武岩纤维增强聚合物(BFRP)棒材的表面特征和混凝土碱度对其劣化以及 BFRP 棒材与海水海砂混凝土(SSC)界面的影响。通过剪切、拉伸和拔出试验,分别研究了嵌入两种碱度海砂混凝土中的具有三种表面特征(砂涂层、螺旋缠绕和螺旋包裹)的玄武岩纤维增强聚合物棒材以及玄武岩纤维增强聚合物棒材与海砂混凝土界面的降解情况。此外,还利用傅立叶变换红外光谱(FTIR)、X 射线计算机断层扫描(X-CT)和扫描电子显微镜(SEM)对 BFRP 和 BFRP-SSC 界面的微观结构进行了表征。实验结果表明,砂涂层 BFRP 钢筋由于形成了砂保护层,在三种类型的 BFRP 钢筋中耐久性能最好,而螺旋缠绕 BFRP 钢筋则从沟槽处(纤维丰富、树脂保护区较少)开始降解。在低碱度(LA)SSC 中,由于碱度降低,BFRP 钢筋的降解明显减轻。此外,与其他两种 BFRP 钢筋相比,砂层的阻碍作用还增强了钢筋与 SSC 之间的粘结耐久性。在海水中浸泡 180 天后,BFRP 钢筋与 LA-SSC 的粘结强度略有降低,而与普通(O)SSC 的粘结强度则显著降低。在环境条件下,LA-SSC 中砂涂层 BFRP 钢筋的拉拔失效表现为砂层和表面树脂的磨损,而在 LA-SSC 中螺旋缠绕 BFRP 钢筋的拉拔失效表现为肋条的剥落。这些研究成果可作为在海洋环境中使用 BFRP 钢筋的坚实基础。



来源:复合材料力学仿真Composites FEM
ACT复合材料电子海洋材料Fourier Transform试验InVEST
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首次发布时间:2024-11-03
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【新文速递】2023年10月16日固体力学SCI期刊最新文章

今日更新:Journal of the Mechanics and Physics of Solids 1 篇,Mechanics of Materials 3 篇,Thin-Walled Structures 1 篇Journal of the Mechanics and Physics of SolidsSouriau’s general covariant formulation of Relativistic Hyperelasticity revisitedKolev B., Desmorat R.doi:10.1016/j.jmps.2023.105463重新审视苏里奥相对论超弹性的一般协变公式We present and modernize Souriau’s 1958 geometric framework for Relativistic continuous media, and enlighten the necessary and the ad hoc modeling choices made since. We focus as much as possible on the Continuum Mechanics point of view and describe the general covariant formulation of Hyperelasticity in (Variational) General Relativity. At this level of generality, different relativistic strain and stress tensors are formulated and discussed. Then, the choice of an observer, through the introduction of a spacetime structure allows us to make deeper insights into the foundations of Continuum Mechanics. 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The new in-line incremental die forming process is a continuous manufacturing process that can provide rapid prototyping of automotive components. This new process combines the pressing and drawing operations. The feasibility of using ultra-high-strength steel (UHSS) sheets to manufacture real automotive components usually produced with the conventional cold-roll forming process was evaluated. Finite-element simulations incorporating the mechanical properties of plasticity and ductile fracture were conducted to validate the new process. The results demonstrated that the proposed forming process efficiently produced automotive components with consistent shapes and lengths, and the simulation outputs were in good agreement with the experimental data in terms of dimensional accuracy and quality. Additionally, sensitivity analyses of process parameters such as friction and die design provide valuable insights for optimizing the newly proposed formation process of UHSS sheets.在本研究中,开发了一种替代传统冷轧成形工艺的方法。新型的在线增量模压成形工艺是一种连续制造工艺,可以提供汽车零部件的快速成型。这种新工艺结合了压制和拉伸操作。对利用超高强度钢(UHSS)薄板制造传统冷轧成形工艺生产的汽车零部件的可行性进行了评价。结合塑性和韧性断裂力学性能进行了有限元模拟,验证了新工艺的有效性。结果表明,所提出的成形工艺能有效地生产出形状和长度一致的汽车零部件,仿真结果在尺寸精度和质量上与实验数据吻合较好。此外,摩擦和模具设计等工艺参数的敏感性分析为优化新提出的超高压钢板成形工艺提供了有价值的见解。来源:复合材料力学仿真Composites FEM

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